Adding wallpaper or replacing outdated and faded wallpaper in your home is a great way to improve the look and atmosphere of any room. If you've got patience and some basic do-it-yourself project skills, you should be able to produce a nearly professional looking wallpapering job in your own home with the right tools.
The most important step in hanging wallpaper is the first - preparing the wall. The walls must be completely smooth and free of bumps, cracks, or crevices. These will show very clearly through the wallpaper. All protrusions need to be sanded off, and all depressions need to be filled using drywall patching filler. The wall must also be clean and completely dry, so the wallpaper adhesive can form a strong bond with the wall. All traces of old wallpaper or peeling paint should also be removed with a solvent or steam cleaner.
Divide your walls into sections, so you can hang smaller and more manageable pieces of wallpaper. This insures you will be able to keep them straight and aligned with the next piece. Cut the paper into sections, and prepare any adhesives you will need. Wallpaper that comes with adhesives already applied usually have a wax paper backing. Start hanging this paper by peeling down the first inch or two, attaching it to the wall, and peeling the paper off as you press each section to the wall.
Plain wallpapers that need additional adhesives should be installed in much the same way, except you will be brushing on the adhesive on each small section as you press it to the wall. This prevents air bubbles and wrinkles, and keeps the paper straight. once a section is done, run a wallpaper roller or rolling pin over it to insure it's completely adhered to the wall. When beginning the next section, be sure that the design on the wallpaper is lined up completely with the prior section.